US10508942B2 - Thermal flow meter - Google Patents

Thermal flow meter Download PDF

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US10508942B2
US10508942B2 US14/439,876 US201314439876A US10508942B2 US 10508942 B2 US10508942 B2 US 10508942B2 US 201314439876 A US201314439876 A US 201314439876A US 10508942 B2 US10508942 B2 US 10508942B2
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Prior art keywords
voltage
flow meter
thermal flow
circuit
fault
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US20150300858A1 (en
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Masahiro Matsumoto
Hiroshi Nakano
Keiji Hanzawa
Satoshi Asano
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Hitachi Astemo Ltd
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Hitachi Automotive Systems Ltd
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Assigned to HITACHI AUTOMOTIVE SYSTEMS, LTD. reassignment HITACHI AUTOMOTIVE SYSTEMS, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: HANZAWA, KEIJI, ASANO, SATOSHI, NAKANO, HIROSHI, MATSUMOTO, MASAHIRO
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
    • G01F1/696—Circuits therefor, e.g. constant-current flow meters
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F1/00—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow
    • G01F1/68—Measuring the volume flow or mass flow of fluid or fluent solid material wherein the fluid passes through a meter in a continuous flow by using thermal effects
    • G01F1/696—Circuits therefor, e.g. constant-current flow meters
    • G01F1/698—Feedback or rebalancing circuits, e.g. self heated constant temperature flowmeters
    • G01F25/0007—
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F25/00—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume
    • G01F25/10—Testing or calibration of apparatus for measuring volume, volume flow or liquid level or for metering by volume of flowmeters
    • G01R31/025—
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/54—Testing for continuity
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/50—Testing of electric apparatus, lines, cables or components for short-circuits, continuity, leakage current or incorrect line connections
    • G01R31/58—Testing of lines, cables or conductors

Definitions

  • the present invention relates to thermal flow meters and in particular to a thermal flow meter in which any break can be detected between a sensor element portion and an integrated circuit.
  • the thermal flow rate sensor described in Japanese Patent Application Laid-Open No. 2011-237456 is known.
  • a bridge circuit that detects heater temperature is provided with a balance adjusting resistor.
  • the potential across the balance adjusting resistor is taken out and this end-to-end potential is received by resistors connected in series in multiple stages.
  • An intermediate potential produced between a resistor and a resistor connected in series in multiple stages can be adjusted by changing the intermediate potential with a switch before taking it out. Even when the resistance value of a resistive element configuring the bridge circuit, the balance of the bridge circuit can be adjusted.
  • a first series circuit made up of two resistors and a second series resistance made up of two resistors are connected in parallel to form a bridge circuit.
  • a wire connects a first output terminal for taking out an intermediate potential of the first series circuit with an amplifier; and another wire connects a second output terminal for taking out an intermediate potential of the second series circuit with an amplifier.
  • These wires are respectively connected, to the ground potential through a resistor.
  • PTL 1 Japanese Patent Application Laid-open No. 2011-237456
  • the conventional example in Japanese Patent Application Laid-open No, 2011-237456 does not give consideration to break detection in a wire between a bridge circuit provided in a sensor element and a drive circuit for the bridge circuit.
  • the conventional example in Japanese Patent Application Laid-Open No. 2012-008014 does not give consideration to break detection in a wire for taking out the end-to-end potential of a balance adjusting resistor.
  • FIG. 4 illustrates the configuration of a thermal flow meter as a comparative example for the explanation of the problems.
  • This thermal flow meter is configured of a sensor element portion 1 and an integrated circuit 14 .
  • the following members are placed in the sensor element portion 1 : a heating element 2 ; a heater temperature detecting bridge circuit 3 composed of a heater temperature detecting resistor 4 whose resistance value varies according to the temperature of the heating element 2 , fixed: resistors 5 , 6 , 8 , and a balance adjusting resistor 7 ; and a temperature difference detecting bridge circuit 9 .
  • the temperature difference detecting bridge circuit 9 is composed of temperature detecting resistors 10 , 13 placed on the windward side of the heating element 2 and temperature detecting resistors 11 , 12 placed on the leeward side of the heating element 2 .
  • the temperature difference detecting bridge circuit 9 detects a temperature difference between the windward side and leeward side of the heating element 2 .
  • the following members are placed in the integrated circuit 14 : a tapped adjusting resistor 15 that takes out the intermediate potential of the end-to-end voltage of the balance adjusting resistor 7 ; an amplifier 16 ; a reference voltage source 18 that supplies reference voltage Vref to the temperature difference detecting bridge circuit 9 ; and an amplifier 19 that amplifies the output of the temperature difference detecting bridge circuit 9 to generate a sensor output.
  • the amplifier 16 detects a voltage difference between the tap voltage Vt of the tapped adjusting resistor 15 and the voltage V 45 between the heater temperature detecting resistor 4 and the fixed resistor 5 .
  • the amplifier 16 then generates drive voltage Vh to the
  • a high resistance is connected between the wire L 4 and the ground in FIG. 4 .
  • the potential of the wire L 4 on the integrated circuit 14 side is brought to the ground potential. This can be utilized to detect the break in the wire L 4 .
  • a problem arises.
  • the potential of the wire L 2 on the integrated circuit 14 side is fixed at the potential of the wire L 3 through the wire L 3 and the tapped adjusting resistor 15 . In this case, the tap position of the tapped adjusting resistor 15 is irrelevant.
  • a configuration makes it impossible to detect a break in a wire connecting a bridge circuit and an amplifier with each other.
  • a circuit element is connected in parallel with a resistor configuring the bridge circuit and input voltage to the amplifier is taken out through the circuit element.
  • the present invention has been made in consideration of the foregoing. It is an object of the present invention to enable break detection in a configuration in which a circuit element is connected between wires for taking out the end-to-end voltage of a resistor configuring a bridge circuit. The break detection is carried out in the wires for taking out the end-to-end voltage of the resistor configuring the bridge circuit.
  • a thermal flow meter of the present invention is provided with: a heating element; and a temperature controlling bridge circuit that is configured of a plurality of resistors and controls the temperature of the heating element.
  • the thermal flow meter controls the temperature of the heating element and detects the flow rate of a fluid.
  • the thermal flow meter includes: a circuit element connected in parallel with at least one resistor configuring the temperature controlling bridge circuit through two wires drawn from both ends of the resistor; a voltage detection circuit that detects that the magnitude of voltage generated between the two wires has become smaller than a first predetermined value; and a fault signal output circuit that, when it is detected at the voltage detection circuit that the magnitude of the voltage has become smaller than the first predetermined value, outputs a signal indicating a fault.
  • the present invention it is possible to detect a break in a wire which is difficult for the heater temperature detecting bridge circuit of a thermal flow meter to detect and thus provide a reliable thermal flow meter.
  • FIG. 1 is a drawing illustrating the configuration of a thermal flow meter in a first embodiment
  • FIG. 2 is a drawing showing the input/output characteristics of a comparator 17 ;
  • FIG. 3 is a truth table showing a break detecting function
  • FIG. 4 is a drawing illustrating the configuration of a thermal flow meter as a comparative example for the explanation of a problem to be solved by the present invention
  • FIG. 5 is a drawing illustrating the configuration of a thermal flow meter in a second embodiment
  • FIG. 6 is a drawing showing the input/output characteristics of comparators 17 , 24 ;
  • FIG. 7 is a truth table showing a break detecting function
  • FIG. 8 is a drawing illustrating the configuration of a thermal flow meter in a third embodiment
  • FIG. 9 is a drawing showing the output characteristic of a thermal flow meter in the third embodiment.
  • FIG. 10 is a drawing showing output values in break detection
  • FIG. 11 is a drawing illustrating the configuration of a thermal flow meter in a fourth embodiment
  • FIG. 12 is a drawing illustrating the configuration of a thermal flow meter in a fifth embodiment
  • FIG. 13 is a drawing illustrating the configuration of a thermal flow meter in a sixth embodiment.
  • FIG. 14 is a drawing illustrating the configuration of a thermal flow meter in a seventh embodiment.
  • FIG. 1 illustrates the configuration of a thermal flow meter in the first embodiment
  • FIG. 2 shows the input/output characteristics of a comparator 17
  • FIG. 3 is a truth table showing a break detecting function.
  • the thermal flow meter in this embodiment is basically identical in configuration with the comparative example shown in FIG. 4 except that the comparator 17 and a switch 20 are added.
  • the comparator 17 and a switch 20 are added.
  • the thermal flow meter is configured of a sensor element portion 1 and an integrated circuit 14 .
  • the following members are placed: a heating element 2 ; a heater temperature detecting bridge circuit 3 composed of a heater temperature detecting resistor 4 whose resistance value varies according to the temperature of the heating element 2 , fixed resistors 5 , 6 , 8 , and a balance adjusting resistor 7 ; and a temperature difference detecting bridge circuit 9 composed of temperature detecting resistors 10 , 13 placed on the windward side of the heating element 2 and temperature detecting resistors 11 , 12 placed on the leeward side of the heating element 2 .
  • the temperature difference detecting bridge circuit 9 detects a temperature difference between the windward side and leeward side of the heating element 2 .
  • the following members are placed: a tapped adjusting resistor 15 that takes out the intermediate potential Vt of the end-to-end voltage of the balance adjusting resistor 7 ; an amplifier (differential amplifier) 16 ; a comparator 17 that detects whether or not the voltage between a wire L 2 and a wire L 3 connected to both ends of the balance adjusting resistor 7 is equal to or lower than a first predetermined value; a reference voltage source 18 that supplies the temperature difference detecting bridge circuit 9 with reference voltage Vref; an amplifier (differential amplifier) 19 that amplifies the output of the temperature difference detecting bridge circuit 9 to generate a sensor output; and a switch 20 that fixes the output voltage of the amplifier 19 at the ground potential.
  • the amplifier (differential amplifier) 16 detects a voltage difference between the tap voltage Vt of the tapped adjusting resistor 15 and the voltage V 45 between the heater temperature detecting resistor 4 and the fixed resistor 5 . The amplifier 16 then generates drive voltage Vh to the heating element 2 .
  • intermediate voltage does not mean the median value between two potentials.
  • the term means a voltage or a potential within a range between two potentials. Therefore, an intermediate voltage or an intermediate potential may be a voltage or a potential deviating from a median value.
  • the input voltage of the comparator 17 is determined by the drive voltage Vh of the heating element 2 , the fixed resistors 6 , 8 , the balance adjusting resistor 7 , and the tapped adjusting resistor 15 . That is, the input voltage of the comparator 17 is a voltage within a predetermined range. This voltage within the predetermined range has a voltage value between voltage V 67 and voltage V 78 .
  • the voltage V 67 is lower than the drive voltage Vh by an amount equivalent to a voltage produced at the junction between the fixed resistor 6 and the balance adjusting resistor 7 .
  • the voltage V 78 is higher than the ground potential by an amount equivalent to a. voltage produced at. the fixed resistor 8 .
  • This voltage value is determined by the tap position of the tapped adjusting resistor 15 .
  • the input voltage of the comparator 17 is short-circuited by the tapped adjusting resistor 15 and thus the input voltage of the comparator 17 is zeroed. That is, when two inputs of the comparator 17 are connected by the tapped adjusting resistor 15 and the wire L 2 or the wire L 3 is broken, the two inputs of the comparator 17 are brought to an identical potential. Therefore, when the input voltage of the comparator 17 becomes equal to lower than a first predetermined value Vth as shown in FIG. 2 , it is determined that the wire L 2 or the wire L 3 is broken. The comparator 17 then brings the output to 1.
  • the comparator 17 configures a voltage detection circuit that detects that the magnitude of voltage between the wire L 2 and the wire L 3 has become equal to or smaller than the first predetermined value.
  • a configuration makes it impossible to detect a break in the wires L 2 , L 3 connecting the bridge circuit 3 and the amplifier 16 with each other.
  • a circuit element (tapped adjusting resistor 15 ) is connected in parallel to a resistor (balance adjusting resistor 7 ) configuring the bridge circuit 3 ; and input voltage to the amplifier 16 is taken out through the circuit element.
  • the tapped adjusting resistor 15 an element composed of a plurality of resistors connected in series in multiple stages and a switch, or the like can be used as the circuit element. This circuit element is used to adjust the balance of the bridge circuit.
  • a terminal for taking out voltage V 67 is formed as a pad PD 1 .
  • a pad PD 14 is formed as a terminal.
  • the pad PD 1 and the pad PD 14 are electrically connected with each other through the wire L 2 .
  • a gold wire or an aluminum wire is used for the wire L 2 and the pad PD 1 and the pad PD 14 are wire-bonded with each other.
  • the pad PD 1 is formed on the sensor element portion 1 side and the pad PP 14 is formed on the integrated circuit portion 14 side, the pad PD 1 and the pad PD 14 being wire-bonded with each other.
  • a break in a wire often occurs in a wire portion (wire-bonded wire portion) connecting the pad PD 1 and the pad PD 14 with each other.
  • the sensor output V SO is fixed at the ground potential by the switch 20 .
  • a fault may be indicated to the controller side by connecting the switch 20 to the power supply side to fix the sensor output V SO at the power supply potential.
  • a signal indicating a fault due to a break is outputted from an output terminal 30 to a higher-level controller through an output signal line 29 for outputting a flow rate signal (sensor output V SO ).
  • the switch 20 configures a fault signal output circuit that outputs a signal indicating a fault.
  • break detection in the wire L 2 and the wire L 3 is referred to.
  • a break in the wire L 1 and the wire L 5 can also be detected.
  • “OK” indicates that break detection is feasible
  • “NG” indicates that break detection is infeasible.
  • the bridge circuit Since in this embodiment, the voltage between the wire L 2 and the wire L 3 is just detected with the comparator 17 , the bridge circuit is not affected at all.
  • a break detection method as described in Japanese Patent Application Laid-Open No. 2012-8014, it is necessary to pass a current through a bridge circuit for break detection. This variation in current can have influence on the balance of the bridge circuit. In this embodiment, it is unnecessary to pass a current through a bridge circuit for break detection and the balance of the bridge circuit is not affected.
  • FIG. 5 illustrates the configuration of a thermal flow meter in the second embodiment
  • FIG. 6 shows the input/output characteristics of comparators 17 , 24
  • FIG. 7 is a truth table indicating a break detecting function.
  • the thermal flow meter in the second embodiment is basically identical in configuration with the thermal flow meter in the first embodiment.
  • the operation of the comparator 17 is modified and a fixed resistor 21 , a switch 22 , a fixed resistor 23 , the comparator 24 , and an OR-circuit 25 are added.
  • the fixed resistor 21 is provided on the left part side of the heater temperature detecting bridge circuit 3 and the fixed resistor 23 is placed in parallel with the fixed resistor 21 in the integrated circuit 14 .
  • the comparators 17 , 24 are provided with band-type comparison characteristics as shown in FIG.
  • the input voltage of the comparator 24 is zeroed and becomes lower than the predetermined voltage because the input voltage of the comparator 24 is connected with the fixed resistor 23 .
  • the break in the wire L 4 can be detected by detecting this voltage change with the comparator 24 .
  • detection can be carried out. This enables break detection in the wire L 4 that is impossible in the first embodiment.
  • the right part and left part of the heater temperature detecting bridge circuit 3 can be made identical in circuitry and thus the symmetry of the heater temperature detecting bridge circuit 3 can be enhanced.
  • the reference voltage source 18 as the power supply to the heater temperature detecting bridge circuit 3 makes it possible to reduce variation in the following voltages: voltage between the wire L 2 and the wire L 3 and variation in voltage between the wire L 4 and the wire L 6 under normal conditions. Further, the detection accuracy of the comparators 17 , 24 can be enhanced. As the result of providing the comparators 17 , 24 with band-type characteristics, various faults can be detected as shown in FIG. 7 . Such faults include abnormal voltage in the reference voltage source 18 and faults of short-circuiting of the wires L 2 , L 3 , L 4 , and L 6 to the power supply or the ground.
  • the heater drive voltage Vh is fixed at the ground potential by the switch 22 and heating control on the heating element 2 is thereby stopped. This is intended to prevent excessive voltage from being applied to the heating element 2 when a fault occurs and it is not always necessary to fix the heater drive voltage Vh at the ground potential. It only has to be possible to keep the heater drive voltage Vh at a low voltage. However, fixing the heater drive voltage Vh at the ground potential can suppress power consumed at the heating element 2 more.
  • a switch 22 that fixes heater drive voltage Vh at the ground potential when a fault is detected may be applied to the embodiments described later as well as the first embodiment. When a fault is detected, heating control on the heating element 2 is thereby stopped.
  • the configuration related to the fixed resistor 21 , the fixed resistor 23 , the comparator 24 , and the OR-circuit 25 may be applied to each embodiment described above and below as appropriate.
  • the comparators 17 , 24 are provided with band-type comparison characteristics and a signal indicating a fault is outputted on occasions: when the input voltages of the comparators 17 , 24 are equal to or lower than the first predetermined value Vth 1 ; and when the input voltages of the comparators 17 , 24 are equal to or higher than the second predetermined value Vth 2 .
  • This configuration may also be applied to each configuration described above and below as appropriate.
  • FIG. 8 illustrates the configuration of a thermal flow meter in the third embodiment
  • FIG. 9 shows the output characteristic of the thermal flow meter in the third embodiment
  • FIG. 10 shows output values obtained when a break is detected.
  • the thermal flow meter in the third embodiment is basically identical with the thermal flow meter in the second embodiment in configuration, except that a digital output circuit 26 is provided.
  • the output of the comparator 17 and the output of the comparator 24 are inputted to the digital output circuit 26 .
  • the digital output circuit 26 receives the output of the amplifier 19 that generates sensor output V SO , the output of the comparator 17 , and the output of the comparator 24 .
  • the digital output circuit 26 then outputs sensor output V SO , and a signal indicating a fault as a digital value.
  • the signal indicating a fault is outputted as the output of the thermal flow meter from the output terminal 30 to a higher-level controller through the output signal line 29 for outputting flow rate signals (sensor output V SO ).
  • the digital output circuit 26 configures a fault signal output circuit that outputs a signal indicating a fault.
  • the output value related to the flow rate obtained when the thermal flow meter is in normal operation is so set that the output value varies between ⁇ 30000 and 30000.
  • the output digital values 32768 and ⁇ 32768 respectively correspond to 2 15 and ⁇ 2 15 .
  • a free range not related to output values indicating a flow rate is present between the output digital values 30001 and 32768 and between the output digital values ⁇ 30001 and ⁇ 32766, Output digital values in these free ranges are used as signals indicating a fault.
  • a signal (output value) indicating a fault is set.
  • the output value is fixed at 32000; and when a break is detected at the comparator 24 , the output value is fixed at 32001.
  • the digital output circuit 26 in this embodiment may be applied to the embodiments described above and below to indicate the occurrence of a break to a higher-level controller by an output digital value.
  • FIG. 11 illustrates the configuration of a thermal flow meter in the fourth embodiment.
  • the thermal flow meter in the fourth embodiment is basically identical with the thermal flow meter in the first embodiment in configuration, except that the heater temperature detecting bridge circuit 3 is composed of the heating element 2 , the fixed resistors 5 , 6 , 8 , and the balance adjusting resistor 7 .
  • the heater temperature detecting resistor 4 is replaced with the heating element 2 .
  • breaks in the wire L 2 and the wire L 3 can be detected as in the first embodiment.
  • FIG. 12 illustrates the configuration of a thermal flow meter in the fifth embodiment.
  • the thermal flow meter in the fifth embodiment is basically identical with the thermal flow meter in the fourth embodiment in configuration. A difference is as follows: a current passed through the heating element 2 is detected from the end-to-end voltage of the fixed resistor 5 ; and this end-to-end voltage is taken out by the amplifier 19 to obtain a sensor output. Also in the embodiment, breaks in the wire L 2 and the wire L 3 can be detected as in the first embodiment. Cases where the wire L 1 or L 5 is broken or the amplifier 16 becomes faulty and drive voltage Vh is zeroed can also be detected.
  • FIG. 13 illustrates the configuration of a thermal flow meter in the sixth embodiment.
  • the thermal flow meter in the sixth embodiment is basically identical with the thermal flow meter in the first embodiment in configuration. A difference is as follows: a fixed resistor 27 is connected to the heating element 2 and a current passed through the heating element 2 is detected from the end-to-end voltage of the fixed resistor 27 ; and this end-to-end voltage is taken out by the amplifier 19 to obtain a sensor output. Also in this embodiment, breaks in the wire L 2 and the wire L 3 can be detected as in the first embodiment. Cases where the wire L 1 or L 5 is broken or the amplifier 16 becomes faulty and drive voltage Vh is zeroed can also be detected.
  • FIG. 14 illustrates the configuration of a thermal flow meter in the seventh embodiment.
  • the thermal flow meter in the seventh embodiment is basically identical with the thermal flow meter in the first embodiment in configuration. A difference is as follows: a thermocouple 28 is placed instead of the heater temperature detecting resistor 4 to detect the temperature of the heating element 2 ; and a thermocouple 29 is placed instead of the fixed resistor 6 . Also in this embodiment, breaks in the wire L 2 and the wire L 3 can be detected as in the first embodiment. Cases where the wire L 1 or L 5 is broken or the amplifier 16 becomes faulty and drive voltage Vh is zeroed can also be detected.

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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Measuring Volume Flow (AREA)
US14/439,876 2012-11-02 2013-10-09 Thermal flow meter Active 2033-12-07 US10508942B2 (en)

Applications Claiming Priority (3)

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JP2012242321A JP5851973B2 (ja) 2012-11-02 2012-11-02 熱式流量計
JP2012-242321 2012-11-02
PCT/JP2013/077414 WO2014069193A1 (fr) 2012-11-02 2013-10-09 Débitmètre thermique

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US10508942B2 true US10508942B2 (en) 2019-12-17

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EP (1) EP2916111B1 (fr)
JP (1) JP5851973B2 (fr)
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JP5851973B2 (ja) * 2012-11-02 2016-02-03 日立オートモティブシステムズ株式会社 熱式流量計
WO2016051941A1 (fr) * 2014-09-30 2016-04-07 日立オートモティブシステムズ株式会社 Capteur de débit d'air thermique
JP6149953B1 (ja) * 2016-02-01 2017-06-21 オンキヨー株式会社 保護回路、及び、スイッチング電源
US10242955B2 (en) * 2016-08-29 2019-03-26 Nxp Usa, Inc. Active tamper detection circuit with bypass detection and method therefor
JP6838227B2 (ja) * 2018-03-09 2021-03-03 日立Astemo株式会社 物理量測定装置
JP6914880B2 (ja) * 2018-03-29 2021-08-04 株式会社豊田自動織機 遠心圧縮機及びメカニカルシール
JP6909764B2 (ja) * 2018-08-24 2021-07-28 日立Astemo株式会社 流量センサ

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CN104755885A (zh) 2015-07-01
EP2916111B1 (fr) 2021-01-13
JP2014092414A (ja) 2014-05-19
EP2916111A1 (fr) 2015-09-09
US20150300858A1 (en) 2015-10-22
EP2916111A4 (fr) 2016-07-06
WO2014069193A1 (fr) 2014-05-08

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